NEW YORK (CNNMoney) — More than one in seven Americans are on food stamps, but the federal government wants even more people to sign up for the safety net program.

The U.S. Department of Agriculture has been running radio ads for the past four months encouraging those eligible to enroll. The campaign is targeted at the elderly, working poor, the unemployed and Hispanics.

The department is spending between $2.5 million and $3 million on paid spots, and free public service announcements are also airing. The campaign can be heard in California, Texas, North Carolina, South Carolina, Ohio, and the New York metro area.

“Research has shown that many people — particularly underserved seniors, working poor, and legal immigrants — do not understand the requirements of the program,” said Kevin Concannon, a USDA under secretary.

The radio ads, which run through June 30, come amid a bitter partisan fight over the safety net program. Republican lawmakers want to reduce funding for the benefit or turn it into a block grant program, which would also minimize the cost. Democrats, however, are not willing to make major cuts.